This is the official blog about the development of OctoMY™, the robot platform for you!

2015-05-16

Big push for the generator project.

I decided to make a push for the GX25 generator project.

First I removed the clutch from the GX25. I will be crafting some kind of frame for the generator assembly and also a converter plate to go on the shaft of the motor.

Next I prepared to make the optical tachometer circuit for the ECU to judge motor speed precisely. I had some luck pointing my manual tachometer to black/white tape on the makeshift plate mounted on shaft. Still TODO: I still need a way to pump initial fuel into cold engine (manual pump), and actuating the choke might be handy in cold weather. But after some new intel (se bottom) I think I have found a way to make the generator act as starter motor as well, eliminating the added complexity of a separate engagement mechanism and separately controlled starter motor. Even better, I get to keep the recoil starter for debugging purposes (I already put it back on). Fun fun.

Next I put an ad out where I proclaim that I want any excess generators or alternators that people may have lying around. This resulted in me getting in contact with a fellow who had a 140AMP 12VDC 2005 mod Volvo V75 alternator for cheap, which I bought.

Next, I put an ad out where I proclaim that I want any excess electircal motors, which has resulted in a few emails from people who want to get rid of motors. So far I didn't get any motors though.

Next, I went dumpster diving, or more correctly, electrical appliance recycling plant scavenging. I will keep the location secret because, oh-boy was there a lot to be found!

3.5 HP 180V 7.5 AMP 5200 RPM Threadmill motor

Ditto

Threadmill motor driver circuit

ACME Screw linear actuator from threadmill.

One of 2 washing machine motors.

And last but not least, I put a question on electronics stackexchange asking what motor I would be looking for to make my generator. I got an excellent answer that I am definitely going to pursue next. In the same fell swoop I asked a question about how to measure the torque vs. RPM curve for my motor collection. Turns out there is something called "prony brake".